Information on Samlex Desktop and Rack Mount Power Supplies

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Desktop and Rack Mount
Switching Power Supplies
and Battery Chargers
Compiled and Formerly Maintained by Robert Meister WA1MIK (SK)
Currently Maintained by Mike Morris WA6ILQ.

Click here or the icon above for the Samlex America web page.

Recently multiple people have reported that Samlex no longer "supports field repair" nor do they "disclose schematics".
Samlex manuals are readily available online but many do not contain a schematic diagram.
This is NOT the way to encourage people to purchase your product.
Your page maintainer has about a dozen of the SEC-100BRM power supplies and a similar number of the SEC-1250UL and SEC-1230UL battery chargers spread across a number of commercial radio sites.
If I can't get a schematic when I need it I'll be looking for a new manufacturer.
Samlex makes REALLY GOOD stuff, I'd hate to have to switch.

Does anyone have a reverse engineered / hand drawn schematic of the SEC-1230UL or SEC-1250UL chargers?
Or the SEC-2012MPSB power supply module? (or any other Samlex units?) Anonymous donations are fine...

Manuals and Useful Information:

SEC-1212 and SEC-1223 Power Supply Manual 2.0 MB PDF file by Samlex
Even though the model number indicates 12A, the SEC-1212 supply is only rated for 10 amps continuous. It relies on convection cooling and has no fan. Because there's no fan, the SEC-1212 illuminated power switch is in the lower right corner of the front panel. Click here for an inside photo (courtesy of Bob WA1MIK).
The SEC-1223 is rated for 23 amps continuous (the only one whose model number and current capability agree) and it has a thermostatically-controlled cooling fan. Since there's a fan inside, the SEC-1223 illuminated power switch is in the lower left corner of the front panel. Click here for an inside photo (courtesy of Bob WA1MIK).
The DC output terminals on both of these models are further apart and more centrally located on the rear panel than they are on the SEC-1235 supply. There is room on the front panel of either unit to add Anderson PowerPoles.
At one time the SEC-1223 was relabeled by Kenwood as the KPS-15-DC.

SEC-1223 Schematic and Parts List 530 KB PDF file redrawn by Tom NØSS
The SEC-1212 and SEC-1235 supplies are similar as are a Kenwood KPS-15 and a Yaesu FP-1023.

SEC-1223BBM Power Supply with Battery Backup Manual 1.7 MB PDF file by Samlex
The same as an SEC-1223 but has an extra pair of terminals to attach to a battery. Provides up to 4A of charging current.

SEC-1235 and SEC-1235M Power Supply Manual 1.6 MB PDF file by Samlex
These supplies are rated for 30 Amps continuous and have a thermostatically-controlled cooling fan. The SEC-1235M has analog voltage and current meters on the front panel and is their only desktop model that has meters. Because of the possibility of meters, the illuminated power switch is on the front right corner above the internal cooling fan. Click here for an inside photo of an SEC-1235M (courtesy of Phil AD5X).
The DC output terminals are closer together and closer to the side of the unit than they are on the SEC-1212 or SEC-1223 supplies.

SEC-12xxP Power Supply Manual 1.3 MB PDF file by Samlex
The SEC-12xxP models are newer versions of the SEC-12xx supplies. They have the same ratings as the SEC-12xx supplies however they will automatically handle 120 or 240VAC input power; no internal jumper change required. The SEC-1235PM has a dual back-lit meter and an illumination on/off switch. The fan, for those supplies that have one, has been relocated to the rear panel of the supply. This manual actually covers all of the SEC-12xxP series switching power supplies.

Samlex desktop switching power supplies have two adjustment pots inside. The one that is closest to the rear of the chassis is labeled VR2 and it adjusts the output voltage. The one that is more centrally located and easier to get to is labeled VR1 and it sets the maximum output current. Most desktop switching power supplies do not have an over-voltage crowbar circuit and neither do the Samlex units, therefore the output voltage can easily be adjusted to 12-16VDC.

Samlex desktop switching power supplies will go into current limiting a few amps above their rated maximum current. When this occurs, the voltage drops down to just a couple of volts but the current remains at the maximum value; it does not fold back as happens in Astron and most other linear power supplies.

A number of the Samlex desktop switching power supplies use odd DC output terminals that fit into 1/2 inch square holes in the rear of the chassis. They accept 5mm round terminal pins. Stranded wires should be twisted and tinned to become a solid wire or crimped into an appropriate terminal pin. They use a 5/64 hex socket set screw that is #10, 24 TPI, 5/16 inch long. A hex key (Allen wrench) is supplied with the power supply. Older supplies used a slotted brass set screw that was easily broken. An M4x0.7 screw also fits.

Samlex desktop switching power supplies produced for 120VAC mains voltage have an internal line fuse with the following ratings:
SEC-1212: 5mm x 20mm Glass Fuse, 250V, 3.0A, Time Delay Type, LittelFuse 239003
SEC-1223: 5mm x 20mm Glass Fuse, 250V, 6.3A, Time Delay Type, LittelFuse 21806.3
SEC-1235: 5mm x 20mm Glass Fuse, 250V, 8.0A, Time Delay Type, LittelFuse 218008
When purchasing these fuses, they often have a "TnA" part number, where "T" stands for "Time Delay" (also known as Slo-Blo) and "n" is the current in amps. See the manual for 240VAC mains fuse ratings.

Eric Lemmon WB6FLY (SK) performed load tests of the Samlex SEC-1212 and the Yaesu FP-1023 (a Samlex SEC-1223 inside) that can be found in the "AC and DC Power-Related Information" section of the Technical Information page of this website.

There is about an inch of room behind the front panel to install a small LED or LCD meter and selector switch, but the metal is pretty thick and it may not be easy to cut a square hole to insert the meter through. See the inside photos above. It might be easier to install an external voltmeter and ammeter, or just buy a supply with meters, such as the SEC-1235M.

Samlex offers a rack mount chassis to hold their desktop switching power supplies. See their web page for further details and models.

Modifications and Datasheets:

SEC-100BRM 13.8 volt 100 amp Rack-Mount Power Supply Specification Sheet 327 kB PDF file
This is the specification sheet for the 100 amp rack mount power supply. These are EXCELLENT units!

SEC-40BRM, SEC-60BRM, SEC-80BRM, SEC-100BRM 13.8 volt 100 amp Rack-Mount Power Supply N + 1 DC Power System Owners Manual 910 kB PDF file
This is the manual for the above 40, 60, 80, and 100 amp rack mount 12 volt power supplies. They also make models with 24 volts output. These are built for 120 volts and the SEC-100BRM-230 model is made for 230 volts AC and they are NOT modifiable for the other voltage. This unit has a front panel voltmeter / ammeter, a fan failure LED (and a annoying beeper), and five green LEDs showing the functionality of the internal 20-amp modules (from two to five) that are in parallel. There are four high current connections on the rear, a red and a white for the DC output and a second set of red and white that are for a backup battery. The two white ground terminals are paralleled inside.

Internal: The 40, 60, 80 and 100 amp units are identical except they are shipped with two, three, four or five SEC-2012MPSB modules. Samlex markets this product line as "N+1 redundancy" because you can add an extra module to the 40, 60 or 80 amp units. The modules are field replaceable however you have to shut down your system, remove teh power supply from the rack, take it to the bench, and spend an hour swapping modules, then reinstall it back into the rack.
Now mind you, they ship a 40 amp unit with two modules, a 60 amp unit with three, and a 80 amp unit with four, so YOU have to purchase and field install a extra module to get N+1. And the 100 amp units have five 20-amp modules inside so you CAN'T ever get N+1 redundancy, that feature dies at the 80 amp level.

Modules: A lower amperage unit can be field upgraded by field installing additional SEC-2012MPSB modules (in 2022 they were about US$80 to $100 each). Note that if you buy a module to replace a failed module or upgrade your power supply the green LED (which has a Samlex-specific connector to plug into the circuit board) is not included, you have to ASK for it!!!

Your page maintainer has about a dozen of the 12 volt 100 amp supplies in commercial mountaintop service, one site has five supplies. I've always ordered a 100 amp unit, the last few times I've received a 40 amp unit plus the other modules in individual wrapping (I've had to assemble the supplies). Note that Samlex WILL NOT provide a schematic of the power supply chassis or of the 20 amp module, if you have one that fails they want you to toss the dead one in the trash and buy new. This is a pet peeve of the company owner, he is exploring his options for different supplies. If anyone has reverse engineered the chassis or the 20 amp module we'll be happy to host your documentation.

Charger: The chassis contains a small constant-voltage trickle charger feature (the charger is not a separate module) that can be easily disabled if the site backup battery has its own charger... however it is NOT a multistage charger, it is a simple constant-voltage trickle charger (4 amps or 8 amps of charging current) two 0.78 ohm power resistors in parallel (use one resistor for 4 amps, both for 8 amps) between the power supply positive output terminal and the battery positive terminal. Depending on the output voltage of the supply and the type of battery it could overcharge or undercharge your battery, and in case of a extended power failure the trickle charger could take a very, very, very long time to recharge your site battery. Your page maintainer uses all 100 amp power supplies and with the internal charger disabled. The battery charging function at our sites is provided by one or two of the SEC-1250UL (50 amps) or SEC-1235UL (35 amps) battery chargers or one SEC-1280UL (80 amp) battery chargers - each site has between 400 and 800 amp-hours of backup battery.

Fans: The two fans in the unit are 12 volt DC fans, 80mm square and 25mm thick. The fans are on one end of a 12 inch 2-wire harness with a Samlex-specific connector on the other end (same connector as the green LED but the pinout polarity is reversed!). Don't throw away the old fan until you cut the wires several inches back from the Samlex-specific connector, you will need to splice the new fan wires onto the salvaged (old) connector. It is a 2-pin 1/10 inch spacing connector: contact side back side. The yellow spot is a bit of glue residue, the factory doesn't want them coming loose in shipping.

We found ADDA brand fans in the older SEC-100BRM units and Jamicon JF0825B1SR-R fans inside the newer supplies. The "B" or a "U" in the same position of the Jamicon part number indicates a ball bearing, an "S" in that position indicates a sleeve bearing (you can find JF0825S1-type fans all over the internet). Cheap fans use brass or bronze bushings or sleeves, cheaper fans use plastic bushings, good fans use metal ball bearings and are worth the extra cost. Make sure you use ball bearing fans from a reputable vendor - and you don't want "ball bearing" fans where the balls are nylon! (Yes, some chinese fans use nylon balls!) A while back a friend bought a SEC-40BRM on eBay, when it arrived he checked the fans, they were not original (the wires were spliced with the Samlex-specific connectors) and had been replaced with ADDA part number AD08012HX2570004.

Rear monitoring connector: There is a 25 pin D-sub female connector on the rear for remote monitoring of the DC voltage output, the DC current drawn, the output of each of the five 20-amp modules, failure of either of the two DC fans, the presence of AC mains power, and more.
The pinout of that connector is here (it's just one page from the manual). There is no single output that indicates a module failure but you can create one by diode-ORing the individual module fail pins. You could add the fan fail pin into that diode-ORing and have one alarm pin for any power supply issue.

SEC-1230UL 13.8 volt 30 amp Multistage battery Charger Spec Sheet 481 KB PDF file
This is the specification sheet for the yellow Samlex 30 amp multistage battery charger.

SEC-1215UL (15 amp) and SEC-1230UL (30 amp) 13.8 volt Multistage battery Charger Manual 2.2 MB PDF file
This is the manual for the yellow Samlex 15 and 30 amp multistage battery chargers.

SEC-1250UL 13.8 volt 50 amp Multistage battery Charger Spec Sheet 447 KB PDF file
This is the specification sheet for the yellow Samlex 50 amp multistage battery chargers.

SEC-1250UL 13.8 volt 50 amp Multistage battery Charger Manual 2.3 MB PDF file
This is the manual for the yellow Samlex 50 amp multistage battery chargers. They also come in 80 amps.
One trick tp tell them apart: The 15 amp and 30 amp charger has one meter, the 50 amp and 80 amp models have two.

SEC-1223 120V to 240V Modification 750 kB PDF file
The other supplies can be similarly modified; the procedure is described in the manuals above. The yellow jumper wire can easily be seen in the two photos above, between the two large filter capacitors.
The newest SEC-12xxP models automatically detect and handle either 120V or 240V input voltages, so no jumper is present in these units.

SEC-1223 RF Filter Modification 720 KB PDF file by Nigel ZL2DF

KA7500B Switching Mode Regulator IC Datasheet 61 KB PDF file
Many Samlex desktop switching power supplies use this IC.

TL494 Switching Mode Regulator IC Datasheet 1.3 MB PDF file
This is functionally equivalent to the KA7500B above and is a very common IC in desktop switching power supplies made by Astron and other companies.

Samlex SEC-1223 Modifications 1.8 MB PDF file
While listed for the SEC-1223, this also pertains to the SEC-1212, SEC-1235, and SEC-1235M power supplies. The yellow 120V/240V jumper is similar in the other models but the pins are labeled with different letters. It also contains an unofficial schematic and parts list. Some of this information is available separately above.

Samlex SEC-1223 Power Supply Repair by Paul Robertson N2XZF 358 KB PDF file
Notes on repairing the Samlex 1223 / Kenwood KPS-15, and possibly the Yaesu FP1023 power supply.

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This page initially created 01-Jul-2020.

This web page, this web site, the information presented in and on its pages and in these modifications and conversions is © Copyrighted 1995 and (date of last update) by Kevin Custer W3KKC and multiple originating authors. All Rights Reserved, including that of paper and web publication elsewhere.

	SEC-1212 and SEC-1223 Power Supply Manual 2.0 MB PDF file by Samlex Even though the model number indicates 12A, the SEC-1212 supply is only rated for 10 amps continuous. It relies on convection cooling and has no fan. Because there's no fan, the SEC-1212 illuminated power switch is in the lower right corner of the front panel. Click here for an inside photo (courtesy of Bob WA1MIK). The SEC-1223 is rated for 23 amps continuous (the only one whose model number and current capability agree) and it has a thermostatically-controlled cooling fan. Since there's a fan inside, the SEC-1223 illuminated power switch is in the lower left corner of the front panel. Click here for an inside photo (courtesy of Bob WA1MIK). The DC output terminals on both of these models are further apart and more centrally located on the rear panel than they are on the SEC-1235 supply. There is room on the front panel of either unit to add Anderson PowerPoles. At one time the SEC-1223 was relabeled by Kenwood as the KPS-15-DC.
	SEC-1223 Schematic and Parts List 530 KB PDF file redrawn by Tom NØSS The SEC-1212 and SEC-1235 supplies are similar as are a Kenwood KPS-15 and a Yaesu FP-1023.
	SEC-1223BBM Power Supply with Battery Backup Manual 1.7 MB PDF file by Samlex The same as an SEC-1223 but has an extra pair of terminals to attach to a battery. Provides up to 4A of charging current.
	SEC-1235 and SEC-1235M Power Supply Manual 1.6 MB PDF file by Samlex These supplies are rated for 30 Amps continuous and have a thermostatically-controlled cooling fan. The SEC-1235M has analog voltage and current meters on the front panel and is their only desktop model that has meters. Because of the possibility of meters, the illuminated power switch is on the front right corner above the internal cooling fan. Click here for an inside photo of an SEC-1235M (courtesy of Phil AD5X). The DC output terminals are closer together and closer to the side of the unit than they are on the SEC-1212 or SEC-1223 supplies.
	SEC-12xxP Power Supply Manual 1.3 MB PDF file by Samlex The SEC-12xxP models are newer versions of the SEC-12xx supplies. They have the same ratings as the SEC-12xx supplies however they will automatically handle 120 or 240VAC input power; no internal jumper change required. The SEC-1235PM has a dual back-lit meter and an illumination on/off switch. The fan, for those supplies that have one, has been relocated to the rear panel of the supply. This manual actually covers all of the SEC-12xxP series switching power supplies.
	Samlex desktop switching power supplies have two adjustment pots inside. The one that is closest to the rear of the chassis is labeled VR2 and it adjusts the output voltage. The one that is more centrally located and easier to get to is labeled VR1 and it sets the maximum output current. Most desktop switching power supplies do not have an over-voltage crowbar circuit and neither do the Samlex units, therefore the output voltage can easily be adjusted to 12-16VDC.
	Samlex desktop switching power supplies will go into current limiting a few amps above their rated maximum current. When this occurs, the voltage drops down to just a couple of volts but the current remains at the maximum value; it does not fold back as happens in Astron and most other linear power supplies.
	A number of the Samlex desktop switching power supplies use odd DC output terminals that fit into 1/2 inch square holes in the rear of the chassis. They accept 5mm round terminal pins. Stranded wires should be twisted and tinned to become a solid wire or crimped into an appropriate terminal pin. They use a 5/64 hex socket set screw that is #10, 24 TPI, 5/16 inch long. A hex key (Allen wrench) is supplied with the power supply. Older supplies used a slotted brass set screw that was easily broken. An M4x0.7 screw also fits.
	Samlex desktop switching power supplies produced for 120VAC mains voltage have an internal line fuse with the following ratings: SEC-1212: 5mm x 20mm Glass Fuse, 250V, 3.0A, Time Delay Type, LittelFuse 239003 SEC-1223: 5mm x 20mm Glass Fuse, 250V, 6.3A, Time Delay Type, LittelFuse 21806.3 SEC-1235: 5mm x 20mm Glass Fuse, 250V, 8.0A, Time Delay Type, LittelFuse 218008 When purchasing these fuses, they often have a "TnA" part number, where "T" stands for "Time Delay" (also known as Slo-Blo) and "n" is the current in amps. See the manual for 240VAC mains fuse ratings.
	Eric Lemmon WB6FLY (SK) performed load tests of the Samlex SEC-1212 and the Yaesu FP-1023 (a Samlex SEC-1223 inside) that can be found in the "AC and DC Power-Related Information" section of the Technical Information page of this website.
	There is about an inch of room behind the front panel to install a small LED or LCD meter and selector switch, but the metal is pretty thick and it may not be easy to cut a square hole to insert the meter through. See the inside photos above. It might be easier to install an external voltmeter and ammeter, or just buy a supply with meters, such as the SEC-1235M.
	Samlex offers a rack mount chassis to hold their desktop switching power supplies. See their web page for further details and models.

	SEC-100BRM 13.8 volt 100 amp Rack-Mount Power Supply Specification Sheet 327 kB PDF file This is the specification sheet for the 100 amp rack mount power supply. These are EXCELLENT units!
	SEC-40BRM, SEC-60BRM, SEC-80BRM, SEC-100BRM 13.8 volt 100 amp Rack-Mount Power Supply N + 1 DC Power System Owners Manual 910 kB PDF file This is the manual for the above 40, 60, 80, and 100 amp rack mount 12 volt power supplies. They also make models with 24 volts output. These are built for 120 volts and the SEC-100BRM-230 model is made for 230 volts AC and they are NOT modifiable for the other voltage. This unit has a front panel voltmeter / ammeter, a fan failure LED (and a annoying beeper), and five green LEDs showing the functionality of the internal 20-amp modules (from two to five) that are in parallel. There are four high current connections on the rear, a red and a white for the DC output and a second set of red and white that are for a backup battery. The two white ground terminals are paralleled inside. Internal: The 40, 60, 80 and 100 amp units are identical except they are shipped with two, three, four or five SEC-2012MPSB modules. Samlex markets this product line as "N+1 redundancy" because you can add an extra module to the 40, 60 or 80 amp units. The modules are field replaceable however you have to shut down your system, remove teh power supply from the rack, take it to the bench, and spend an hour swapping modules, then reinstall it back into the rack. Now mind you, they ship a 40 amp unit with two modules, a 60 amp unit with three, and a 80 amp unit with four, so YOU have to purchase and field install a extra module to get N+1. And the 100 amp units have five 20-amp modules inside so you CAN'T ever get N+1 redundancy, that feature dies at the 80 amp level. Modules: A lower amperage unit can be field upgraded by field installing additional SEC-2012MPSB modules (in 2022 they were about US$80 to $100 each). Note that if you buy a module to replace a failed module or upgrade your power supply the green LED (which has a Samlex-specific connector to plug into the circuit board) is not included, you have to ASK for it!!! Your page maintainer has about a dozen of the 12 volt 100 amp supplies in commercial mountaintop service, one site has five supplies. I've always ordered a 100 amp unit, the last few times I've received a 40 amp unit plus the other modules in individual wrapping (I've had to assemble the supplies). Note that Samlex WILL NOT provide a schematic of the power supply chassis or of the 20 amp module, if you have one that fails they want you to toss the dead one in the trash and buy new. This is a pet peeve of the company owner, he is exploring his options for different supplies. If anyone has reverse engineered the chassis or the 20 amp module we'll be happy to host your documentation. Charger: The chassis contains a small constant-voltage trickle charger feature (the charger is not a separate module) that can be easily disabled if the site backup battery has its own charger... however it is NOT a multistage charger, it is a simple constant-voltage trickle charger (4 amps or 8 amps of charging current) two 0.78 ohm power resistors in parallel (use one resistor for 4 amps, both for 8 amps) between the power supply positive output terminal and the battery positive terminal. Depending on the output voltage of the supply and the type of battery it could overcharge or undercharge your battery, and in case of a extended power failure the trickle charger could take a very, very, very long time to recharge your site battery. Your page maintainer uses all 100 amp power supplies and with the internal charger disabled. The battery charging function at our sites is provided by one or two of the SEC-1250UL (50 amps) or SEC-1235UL (35 amps) battery chargers or one SEC-1280UL (80 amp) battery chargers - each site has between 400 and 800 amp-hours of backup battery. Fans: The two fans in the unit are 12 volt DC fans, 80mm square and 25mm thick. The fans are on one end of a 12 inch 2-wire harness with a Samlex-specific connector on the other end (same connector as the green LED but the pinout polarity is reversed!). Don't throw away the old fan until you cut the wires several inches back from the Samlex-specific connector, you will need to splice the new fan wires onto the salvaged (old) connector. It is a 2-pin 1/10 inch spacing connector: contact side back side. The yellow spot is a bit of glue residue, the factory doesn't want them coming loose in shipping. We found ADDA brand fans in the older SEC-100BRM units and Jamicon JF0825B1SR-R fans inside the newer supplies. The "B" or a "U" in the same position of the Jamicon part number indicates a ball bearing, an "S" in that position indicates a sleeve bearing (you can find JF0825S1-type fans all over the internet). Cheap fans use brass or bronze bushings or sleeves, cheaper fans use plastic bushings, good fans use metal ball bearings and are worth the extra cost. Make sure you use ball bearing fans from a reputable vendor - and you don't want "ball bearing" fans where the balls are nylon! (Yes, some chinese fans use nylon balls!) A while back a friend bought a SEC-40BRM on eBay, when it arrived he checked the fans, they were not original (the wires were spliced with the Samlex-specific connectors) and had been replaced with ADDA part number AD08012HX2570004. Rear monitoring connector: There is a 25 pin D-sub female connector on the rear for remote monitoring of the DC voltage output, the DC current drawn, the output of each of the five 20-amp modules, failure of either of the two DC fans, the presence of AC mains power, and more. The pinout of that connector is here (it's just one page from the manual). There is no single output that indicates a module failure but you can create one by diode-ORing the individual module fail pins. You could add the fan fail pin into that diode-ORing and have one alarm pin for any power supply issue.
	SEC-1230UL 13.8 volt 30 amp Multistage battery Charger Spec Sheet 481 KB PDF file This is the specification sheet for the yellow Samlex 30 amp multistage battery charger.
	SEC-1215UL (15 amp) and SEC-1230UL (30 amp) 13.8 volt Multistage battery Charger Manual 2.2 MB PDF file This is the manual for the yellow Samlex 15 and 30 amp multistage battery chargers.
	SEC-1250UL 13.8 volt 50 amp Multistage battery Charger Spec Sheet 447 KB PDF file This is the specification sheet for the yellow Samlex 50 amp multistage battery chargers.
	SEC-1250UL 13.8 volt 50 amp Multistage battery Charger Manual 2.3 MB PDF file This is the manual for the yellow Samlex 50 amp multistage battery chargers. They also come in 80 amps. One trick tp tell them apart: The 15 amp and 30 amp charger has one meter, the 50 amp and 80 amp models have two.
	SEC-1223 120V to 240V Modification 750 kB PDF file The other supplies can be similarly modified; the procedure is described in the manuals above. The yellow jumper wire can easily be seen in the two photos above, between the two large filter capacitors. The newest SEC-12xxP models automatically detect and handle either 120V or 240V input voltages, so no jumper is present in these units.
	SEC-1223 RF Filter Modification 720 KB PDF file by Nigel ZL2DF
	KA7500B Switching Mode Regulator IC Datasheet 61 KB PDF file Many Samlex desktop switching power supplies use this IC.
	TL494 Switching Mode Regulator IC Datasheet 1.3 MB PDF file This is functionally equivalent to the KA7500B above and is a very common IC in desktop switching power supplies made by Astron and other companies.
	Samlex SEC-1223 Modifications 1.8 MB PDF file While listed for the SEC-1223, this also pertains to the SEC-1212, SEC-1235, and SEC-1235M power supplies. The yellow 120V/240V jumper is similar in the other models but the pins are labeled with different letters. It also contains an unofficial schematic and parts list. Some of this information is available separately above.
	Samlex SEC-1223 Power Supply Repair by Paul Robertson N2XZF 358 KB PDF file Notes on repairing the Samlex 1223 / Kenwood KPS-15, and possibly the Yaesu FP1023 power supply.